Table 3.
Cord and maternal blood mercury levels [mean ± SD (no.)] by proximity of residence or employment location to the WTC site in the 4 weeks after 11 September 2001.
| Group | Cord total Hg (n) | Maternal total Hg (n) |
|---|---|---|
| Within 2 miles of the WTC in the 4 weeks after 11 September | ||
| Resided | 9.46 ± 11.28a,b (73) | 2.48 ± 2.42 (54) |
| Employed | 4.67 ± 4.40a,b (46) | 2.23 ± 2.31 (45) |
| Reference | 7.97 ± 9.88a (161) | 2.27 ± 2.26 (113) |
| Within 1 mile of the WTC in the 4 weeks after 11 September | ||
| Resided | 10.6 ± 11.4 (18) | 3.4 ± 2.8 (12) |
| Employed | 5.7 ± 5.5 (35) | 2.6 ± 2.8 (34) |
| Reference | 7.9 ± 10.0 (227) | 2.2 ± 2.1 (166) |
No significant trend in log-transformed cord or maternal mercury in the three 1- or 2-mile groups (OLS regression); no significant difference in maternal mercury in the three 1- and 2-mile groups, Kruskal–Wallis Test.
a
p = 0.047 for difference in unadjusted log cord mercury in the three 2-mile groups, Kruskal–Wallis test.
b
p = 0.013 for difference in unadjusted log cord mercury between residential and employed group, Mann–Whitney test.